powerpc/512x: clk: Include clk.h

This clock provider uses the consumer API, so include clk.h
explicitly.

Cc: Gerhard Sittig <gsi@denx.de>
Cc: Scott Wood <scottwood@freescale.com>
Acked-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

arch/powerpc/platforms/512x/clock-commonclk.c

@@ -12,6 +12,7 @@
  */
 
 #include <linux/bitops.h>
+#include <linux/clk.h>
 #include <linux/clk-provider.h>
 #include <linux/clkdev.h>
 #include <linux/device.h>